Michael l



(No Model.) I

M. L. POWERS.

MACHINERY FOR GRINDING AND POLISHING THE HANDLES 0F GUTLBRY No. 399,208. Patented Mar. 5, 1889 liNiTED STATES PATENT @FFTCEG MICHAEL L. POXVERS, OF MILLERS FALLS, HASSi-XCHUSETTS, ASSIGNOR TO PATRICK O. KEEF i, ()F SAME PLACE.

SPECIFICATION forming part of Letters Patent No. 399,208, dated March 5, 1889.

Application filed July 26, 1387.

To all whom it may concern-.-

Be it known that 1, MICHAEL L. Pownns, a citizen of the United States, residing at Millers Falls, in the county of Franklin and State of Massachusetts, have invented certain new and useful Improvements in Machinery for Grinding and Polishing the Handles of Cutlery; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will, enable others skilled in the art to which it appertains to make and use the same.

My invention is an improvement in machinery for grindin g and polishing the handles of case or table knives.

()ne of the important features of my machine the knife-holder, which consists of a mandrel, having an interior form suitable to the reception of the blade and bolster of the knife, (the end of the former being centerable therein and the latter being held loosely to place,) while the part of the knifc the handle to be operated upon-cxtends outside of said mandrel and in front of the grindinguvhecl. The two parts which form the holding portion of the mandrel are made of spring material, so that the hold taken upon the knife will not be rigid, but yielding, to compensate for the action of the said handle between the grindin g-cylindcr and the device for holding said handle in contact with said grinding-cylinder. The mandrel is journaled in a loose journal fitted in a slot which, when the capping of said slot is removed, may be taken out if itis desirable to substitute for said mandrel one of a. differentbolster-notch.

The base, or that portion of the machine which supports and holds the grinding-cylinder, is rigid, and upon said base sets, movable in ways, the carriage which supports and holds the knife-holding mandrel and the several shafts to which are fixed the gear wheels which transmit motion to the said mandrel and receive motion from the source of power. The shaft which carries the driver of these gear-wheels provided with an elliptical cam, which twice in a revolution of said shaft gives maximum mot-ion to a bar, guided properly in a slot, on. the end of which is pivoted a rocking 1)l'(SS6l fOOiJ which contacts longitudinally with the knife-handle being Serial No. 245,345. (No model.)

ground, holding it to place against the grinding-wheel; or the movable carriage may have attached to it beneath the mandrel, or at some other convenient point, a cord or belt which rises and passes over a pulley fixed upon a shaft, and at the free end of said belt or cord is secured a weight by which said movable carriage is yieldingly held, with the several parts ofthe machinery which it carries, to proper position with reference to the grinding-cylinder.

In my drawings illustrating my invention, Figure 1 is a plan or top view of my machine. Fig. 2 is a section on line gr; of Fig. 1; and Fig. 3 is a section on line y y of said figure, looking in the direction of arrow at.

Similar reference-letters indicate like parts in all of the figures.

Referring to the drawings, A is the bed-plate or fixed portion of the machine, to which fixed uprights R for the support of the grindin gcylin der P. These uprights R are secured by screws 7) b to a base which may be detached from the bed-plate A when it is necessary to substitute one kind of grinding-surface for another. The bed-plate A is provided with cleatsA on its transverse edges to to rm a time tail to receive and guide the dovetailed base of the movable carriage B. The carriage l; is formed in the main of a skeleton base, (2, and upright side blocks, f ff to the latter of which journal-bearings are provided for the several rotary shafts. The bed-plate A is provided with a knee or stop, F, to limit the back movement of the carriage B.

N is the mandrel, fixed on a shaft journaled in a square bearin g adjustable in a slot formed in the side block, S, of the carriage B. The mandrel N is bifurcated and its interior is formed in a manner suitable to receive and hold the blade and bolster of the knife to be ground or operated upon. The arms 9' g of this mandrel are made springy. The notch at the base of the mandrel is formed so as to center the knife by the end of the blade, and at the extremity of the mandrel the notch is formed so to hold the bolster of the knife.

0 is a plate fixed to the carriage B, provided with. a longitudinal slot which guides a bar, C, having pivoted thereto a pressenfoot, l).

ing.

A shoulder is formed on the end of the bar C, and the front 1110V01l'16l'1i3 of said bar is limited by a slot, I), formed in the plate (1.

K is the driving-shaft of the machine, journaled in the two upright blocks of the carriage and also in a third or intermediate bear- The shaft is provided with a band or gear-wheel, ll, an elliptical cam, G, and a gear-wheel, I. The said elliptical cam c011- tacts with the bar G as it revolves and throws it toward the grindiiig-eylinder to cause the presser-foot D to accommodate itself to the irregular form. of the knife-handle as the latteris being revolved in front of the said grinding-cylinder.

K is the mandrel-shaft, provided with gearwheel M.

L is an intermediate gear-wheel, forming I \Vhen the knife is adjusted to place in the mandrel, the latter is set in motion by means of the several gear-wheels from the source of power, and by suitable means, unnecessary to be shown, the grinding-cylinder is simultaneously revolved. The presser-foot D is kept bearing against the knifehandle during its movement by means of the elliptical cam G, which, during the rotation of the main shaft, bears constantly against the barto which the presser-foot is pivoted. The presser-foot, by reason of its being readily movable about its axis, yields to the irregular surface of the knife-handle, butat the same time under the influence of the elliptical cam is kept firmly ing mandrel or knife-holder composed of a,

shank j ournaled in the supporting-frame and provided with a gear-wheel, and extending from said shank two spring-fingers formed, substantially as described, and adapted to hold the blade of the knife between them while the handle projecting outside of said mandrel is being acted upon by the grindingcylinder, as and for the purpose set forth.

2. In a machine for grinding and polishing case or other table-knife handles, the combination, with the sliding carriage 13, held to place by means of a cord and weight, substantially as described, of the bar 0, inclosed in plate 0, the presser-foot pivoted to said bar and the cam fixed to the driving shaft, as and for the purpose specified.

The combination, with the base or bed plate provided with guidecleats and having a grinding-cylinder fixed thereon, of the carriage movable upon the said base, the knife holder or mandrel, substantially as described, the gear-wheels for rotating said knife-holder, and the elliptical cam fixed upon the drivingshaft to operate the presser-foot during the revolution of the knife, substantially as and for the purpose set forth.

MICHAEL L. POWERS.

IVitn ess es:

JAMES S. GRINNELL, PATRICK O. KEEFE. 

